Going over this http://sites.google.com/site/h2obsession/CBM/C128/Interlace
(i think it's hydrophilic's site?), I noticed this -> "Update:AmiDog reports an even more fantastic color distortion on PAL systems with the appropriate (wrong for proper interlace) settings. It seems a good PAL hack could produce a new color pallette for the VIC-IIe! "
Is this the same technique discovered at least as far back as 2001 ( @ Risen From Oblivion (VIC parts) comes to mind, as seen here - http://noname.c64.org/csdb/release/?id=2942
The comments seen at the csdb link seem to suggest it is the same material :
"Submitted by DeeKay on 26 November 2006
Amidog: Frankly, we don't quite know ourselves! ;-) Crossbow was experimenting with that $d030-bit that almost all of the effects in the demo are based on and he noticed the colors came out different under certain conditions, because that bit forces an early restart of the screen and seriously fucks with the video signal. It does not work on every monitor we've noticed, some (Philips?) show the original colors!"
"Submitted by Graham on 3 December 2006
The new colors work because of the PAL color encoding: The color carrier consists of U (blue-yellow color distance) and V (red-cyan color distance) which are simply added together, so C = U + V. Now, because a decoder needs to seperate U and V again, the inventors of PAL used a simple trick: They inverted the sign of V every 2nd rasterline, so you always have C = U + V followed by C = U - V. This way you can simply take the color carrier of the previous rasterline and add or subtract the current rasterline with it. If you add both carriers you get back U, and if you subtract you get V or -V. Now, if you skip an odd number of rasterlines, you get -V where normally would be +V and you get +V where normally would be -V. -> The red-cyan color distance gets inverted."
..and so forth...
Any modern updates regarding this trickery?
EDIT: I'm sure the VDC parts of Risen From Oblivion are well known here but just in case : http://noname.c64.org/csdb/release/?id=44983